Lab: Investigating pH of Various Household Products Objective is to determine the pH of common household substances and use this information to identify the substance as an acidic, basic or neutral solution.

Vocabulary Building: be sure that you can define these terms before doing the lab Solvent Solute Solution Aqueous Dissociate Hydrogen ion Hydroxide ion Neutral Solution Acidic Solution Basic Solution

Water in a Glass How do the Molecules appear? Diagram below shows Water molecules with 2 hydrogen Atoms and 1 oxygen atom Above is a diagram of the way in water molecules can look in the glass to the left. The water molecules breaks into ions, hydroxide and hydrogen.

Materials Need an “indicator” which is something that detects the presence of a certain substance Paper Indicators to determine if solution is acid/base: 1. pH paper *indicates the presence and amount of H+ 2. litmus red paper 3. litmus blue paper

Set up for the Lab Test tubes contain various household substances

Above you can see the three types of papers Above you can see the three types of papers. The pH paper is the light yellow colored paper. The red paper is red and the blue paper is blue. A beaker of distilled water is available to clean the stirring rod after each application of a substance on the paper. Preventing contamination of solutions is very important.

Data Table 2 indicates the type of solution for a given household product Solution Guess Acid Base Neutral Milk x Vinegar Egg white Orange Juice Ammonia Unknown #1 Unknown #2 Unknown #1 – Baking Soda Water Unknown #2 – Lemon Juice

Data Table 1: Color of Paper Indicator With a Given Household Product Solution pH Paper Litmus Red Litmus Blue Milk 6-7 Red Vinegar 1-2 Egg white 7-8 Blue Orange Juice 4 Ammonia 9 Unknown #1 8-9 Unknown #2

Part b: Neutralization Reaction Phenolphtalein is another indicator. It will go from colorless to pink if the solution becomes basic. What does that mean to say a solution is basic? In this part, you will use this indicator to demonstrate a neutralization reaction.

Equation for a Neutralization Reaction In our lab, we used ammonia to create a basic solution. Then we added Vinegar until the solution was not longer basic.